Press bed-movement



J. w. WEAVER PRESS BED MOVEMENT.

APPLICATiOil FILED JUNE 26, 1 920.

7 I (I 1,380,446, EazeniedJune 7, LL21.

3 SHEETS-SHEET 1 W/T/VfSSES INVENTOR JTW Wa 2 67;

,4 TTOR/VEYS J. W. WEAVER.

PRESS BED MDVEMENT.

APPLICATION FILED JUNE 26, 1920.

1,380,446. Patented June 7,1921.

3 SHEETS-SHEET 2.

l/Vl/E/VTOH :7. W "Weaver fwy A TTORNEYS WI TNESSES Patented June 7, 1921.

3 SHEETS-SHEET 3.

v INVENTOH J W Wadi/e1:

WITNESSES BY (aw/ 6 ATTORNEYS UNHTED STATES PATENT QFFIQ PRESS BED-MOVEMENT.

To all whom it may concern:

Be it known that 1, JOHN VVILLIS lVnAvnR, a citizen of the United States, and a resident of Raleigh, in the county of lVake and State of North Carolina, have invented certain new and useful Improvements in Press Bed- Movements, of which the following is a specification.

.My invention relates to mechanical movements and has reference more particularly to bed movement mechanism of one and two revolution cylinder printing presses, and all other machinery requiring horizontal reverse action of uniform speed, precision and accuracy.

An object of my invention is to provide simplicity of mechanism, and economy in motive power with minimum wear.

Another object is to provide stationary bearings of the driving pinion wheel with continuous mesh of said pinion wheel and gear teeth in a continuous alternating rack.

Another object is to provide an automatic reverse action at the ends of the alternating rack without jamming or straining.

Another object is to place the drive under the bed in the exact center of load with ample room for bolstering. press bed for rigidity of impression.

Another object is to provide means whereby in a printing press of the character specified great speed of reciprocal action may be attained with mechanical accuracy and durability.

With these and other objects in view my invention consists in certain novel features of construction, arrangement of parts as will be hereinafter fully described, and

pointed out in the claims, reference being had to the accompanying drawings, in which- 1 Figure 1 is a side elevation of the device embodying my improvements,

Fig. 2.is.a similar view of the device from p the opposite side,

Fig. 3 is a vertical transverse section taken 011 the line 33 of Fig. 2,

Fig. 4 is a detail section taken on line 4% of Fig. 2,

Fig. 5 is a vertical section on line 5-5 of Fig. 1,

Fig. 6 is a vertical transverse section taken on line 6+6 of Fig.2,

Fig. 7 is a detail verticalsectiontaken on line 7-7 of F ig. 3,

Specification of Letters Patent.

Application filed June 26, 1920.

Patented J une 7, 1921.

Serial No. 392,131.

Fig. 8 is a detail sectional view showing a form of cushion used. i

Fig. 9 is a perspective view of the rocking lever, detached from the press;

Fig. 10 is a similar view of one of the sectors for aiding movement of gear rack.

Referring more specifically to the drawings which show an embodiment of theinvention as applied to a one or two-revolution cylinder printing press, the frame work of the press is designated generally by the reference character 20, this frame work having the horizontal tracks 21 upon which travels the press bed 22, the bed being provided with the wheels 23 on opposite sides gnccll adjacent the longitudinal ends of the Depending from the underside of the bed at opposite ends are the stationary brackets 24; connected at their lower ends by a beam or bar 25 upon which are placed the cushions 26, the purpose of which will here inafter appear as will that of similar cushions 27 secured to the under surface of the 1' press bed and in alinement with the cushions 26. I

The inner vertical or opposing faces of brackets 24 are faced with metal strips 28 having ears 29 projecting from their side edges at right angles thereto in pairs, the pairs being spaced apart from each other, and the whole constituting vertical guideways within which the ends of a rack-plate 30 may have vertical guided movement. This rack-plate 30 is rectangular in contour and slides vertically as will be understood, by its relation to the guideways just described. This rack-plate which has a reciprocal back and forth movement is cutout to form what may be termed an elliptical rectangle; that is, the rectangular opening is rounded at its ends into semi-circles 31, the entire opening being provided with continuous internal gear teeth; as before stated, the end of the opening is cut on a semi-circle 31 and the'gear teeth at these ends are cut on a semi-circle whose radius is one-half the distance between the parallel sides of the opening. To prevent interference the corners of the teeth in these semicircles may be rounded. I It is mechanically desirable that the opening inthe alternating rack formed of upper rack 32 and lower rack 33, thatis the space between the straight racks,be as narrow as practicable so that the pull will be as near the bed as possible.

The driving mechanism comprises pinion 34 positioned approximately beneath the center of the reciprocating bed 22, said pinion being rigidly secured to a shaft 35 mounted in stationary bearings on the rigid blocks 36 and 37-bolted to the base 38 on which the whole assembly is installed.

The gear pinion 34 is relatively small to insure a practical mesh in the semi-circles 31 at the ends of the endless or continuous rack, and also will require less motive power to drive the bed, and tend to malre the reverse action more flexible. The gear teeth on the alternating rack should be in multiples of the number of gear teeth on the main drive pinion gear in which they mesh, for instance, if the drive pinion has fifty teeth the rack should contain two hundred, two hundred and fifty, three hundred, or three hundred and fifty teeth, as the case may be in accordance with the desired length of gear surface on the rack, this to be governed by the travel required. In other words, each tooth in the drive pinion should be timed to mesh at the same point in the alternating rack each time the drive pinion travels the entire distance of said rack. The number and size of the gear teeth in both the rack and the pinion are to be determined by their proper timing with the cylinder (not shown) of the make of press to which the device is to be adapted. The endless rack is provided with an incasing frame sufficiently strong to insure perfect rigidity with the bed of the press.

As before stated, the drive pinion is mounted on. stationary bearings, and it is held in continuous mesh with the teeth on the alternating rack by the control bar l0, attached to said rack, from which it will be seen that the drive pinion 34: is not shifted at all, as is usual in this type of printing presses, in unmeshing with the upper aclr to another position, and meshing. with the lower rack, in order to produce the reverse action.

By mounting the driving pinion on the shaft 35 which is carried in stationary bearings, the shaft having no longitudinal movement and maintaining the pinion in continuouse mesh with the rack, its position in the center of the load is arbitrarily retained, thus giving a positive, direct and. uniform drive.

The control bar 40 is rigidly secured at one side of the vertical plane of the rack plate by means of yokes 41, which are rigidly secured at their upper and lower ends, to the rack plate and at their centers to the said control bar. This control bar controls the'movements of the alternating rack, in carrying the bed back and forth, by contact with a riding roll 42 carried on the end of shaft 35 beyond the drive pinion 34, as more clearly shown in Figs. 2 and 3, it being noted that the control bar and the riding roll are in constant contact, thus relieving the geared surfaces of undue pressure.

he additional provision against the shock of the bed reverse, I provide the curved shoes d3 at the ends of the rack and facing the ends of the control bar whose ends form inner shoes, the curved shoes being made of a fine grade of steel and subject to fine adjustment, preferably with set screws. The main purpose of these curved shoes as is to overcome the tendency of the riding roll 42 to lose contact with the control bar at the semi-circular ends of the alternating rack. Since contact of the riding roll with these end shoes would reverse the riding roll to the opposite direction and conflict with the control bar, it is necessary to provide another roll 44- at the end of the drive pinion shaft 35 which 1 term a shoeroll, to carry the surplus weight. As will be noted these shoes 43 are attached to the alternating raclrso as to aline with the curved shoe rolls 44.

Depending from the press bed 22 and spaced from each other are the perforated brackets 4L5 and 4L6, between, and in which the rocking lever l7 has a pivotal bearing; one arm as of the lever has pivotal connection with one face of the rack plate by a pin 49, while the other arm 50, which is in a parallel plane with arm 4L8 has at its free end a lateral lug or projection 51, to which is hooked one end of the rack-supporting compression spring 52, the lower end of .aid spring being provided with loop 53 which catches in a notch 54: cut in the lower end of a rigid anchor bar 55 secured at its upper end to the press bed.

The main function of this spring, which may be designated a lifting spring is to insure poise of the rack plate and equalize the contact pressure on the working surface of the control bar. Furthermore, when 'the alternatingraclr in high position the surplus weight of said rack holds the control bar down on the riding roll' when the alternating rack is in low position, the surplus pull of the rack supporting spring 52 holds the control bar up against the riding roll. To provide for the uniform contact of the riding roll, with the control bar at the ends of the alternating rack, air cushions may be provided.

To one face of the endless rack plate at the opposite ends thereof and adjacent the guides thereof, I. provide similar vertical rack plates 56, that is, these plates are of the same length and are provided with exactly the same number and size teeth or serrations which are to be engaged by gear segments 5'? rigidly secured to the opposite ends of a rod 58 rotatably mounted bearings 59 secured to and suspended beneath the bed 22. By use of the vertical rack plates 56 rod 58 and the gears 57 carried at the ends thereof, simultaneous action is produced at both ends of the endless rack-30 when it is raised and "lowered at the opposite ends of the bed travel, thus producing smoothness of action and preventing binding.

At the ends of the press, buffers 60 are provided to relieve the shock when the bed is reversed to the opposite direction, their purpose being to resist the shock of the ed reverse and prevent pressure on the geared surface at the ends of alternating rack; and also preserve a uniform contact on the control bar 4-0.

These buffers may be air cushions and should be constructed to automatically increase resistance as the oscillating move ment of the bed increases in speed.

It will be seen that the alternating rack with control bar and the drive pinion with the riding roll are self contained and art in perfect harmony with each other; the control bar 40 which dominates the alternating rack, revolves around the riding roll a2 and on the drive pinion shaft 35 and is as if held to a common center, the riding roll acting centripetally, and balancing the centrifugal tendency of the alternating rack weight and the rack supporting spring. By such reciprocal action the necessary motive force to drive the press is reduced to a minimum and the resultant wear on working surface becomes almost negligible.

Power being applied to drive shaft 85 the pinion is rotated continuously in the direction indicated by the arrow; this as shown meshes with the lower reach of the rack and carries the rack and the bed to which it is securedtoward the end, the control bar riding on the roll 42; when the curved end of the rack reaches the pinion 34, it starts to ride up the curved end; this pulls the rack down between theguides 29, the segmentalgears 57 at each end of rod 58 meshing in the gear plates 56 so that the movement of the opposite ends is uniform; the pinion continuing along the curved rack, or rather, the rack traveling on the pinion, the rack now commences to move in the reverse direction the control bar now passing beneath the roller .42, the shoes at ends of control bar having guided the roller i l; into proper place.

VVhile'the pinion 34: is shown as rotating continuously to the left, it should be understood that in some presses it may be required to rotate to the right.

Also that there are times when any press must be turned either way in getting certain positions.

Hence I do not limit myself to a driving mechanism in which the driving pinion rotates continuously in one direction only.

i the center of I claim 1. A mechanical movement comprising a main driving pinion, a reciprocating bed member, an endless internal rack suspended from said bed member, said pinion adapted to engage said rack at every point without altering its position relative to its mounting, a control bar carried within said internal rack, curved reversing shoes projecting toward the opposite ends of said control bar but laterally offset from vertical plane thereof, a riding roll mounted on the shaft of the driving pinion, and reversing means for said bed, said means including a shoe-roll mounted on the pinion shaft beyond the riding roll and adapted to engage the aforesaid' curved reversing shoes.

2. In a mechanical movement the combination of a reciprocating bed'inember, a rack-plate suspended therefrom and mounted to have vertical movement independent of the bed, said plate including top and bottom gear racks connected at their ends'by arcuate gear racks of similar pitch, ,a driving pinion mounted to rotate continuously and meshing with said gear racks, a riding roll carried on the shaft of said pinion, a horizontal control bar mountedin the center between said top and bottom gear racks and means for causing the control bar to raise and lower, and travel in contact with the riding roll, said means including intermeshing gear parts carried respectively by the bed and the rack plate.

3. In a mechanical movement, the combination of a reciprocating bed, of an endless internal gear rack suspended from said bed and mounted to slide vertically relatively thereto, a main drive pinion mounted below the bed when in its neutral position, and in mesh at all times with some portion of said internal gear rack, and means for periodically raising and lowering said rack whereby to reverse the direction of travel of bed, said means including vertical racks at opposite ends of the rack plate and rotatable gear segments suspended from the bed, said vertical racks and gear segments intermeshing.

4. In a mechanical movement, the combi-.

nation of a reciprocating bed member, stationary brackets depending therefrom, an endless internal gear rack, slidably connected to said brackets and vertically movable thereon. a main driving pinion rotating conti'nuously in the same direction and meshing with said internal gear rack, and cushion means limiting the upward and downward play of said rack.

5. In a mechanical movement, the combination of a reciprocating bed member, sta-- tionary bracket arms pendent from said bed and spaced apart longitudinally of the bed, a bar bridging the lower ends of said bracket arms, vertical guide means mounted on said bracket arms, cushions mounted on the under face of said bed and on said bridge bar, a plate slidably mounted in the aforesaid bracket arms and cooperating with the guide means, said plate having an elliptical internal gear rack, in a transverse opening therethrough, a main driving pinion mounted to rotate continuously in same direction and meshing with said internal gear rack, a control bar carried by said plate within the said opening, a riding roll mounted on the shaft of the driving pinion and rotatable thereon independent of the pinion, said riding roll adapted for engagement with said control bar at all times, and riding roll shoes adjacent the ends of said control bar for engagement with said riding roll, to assist in the vertical movement of the rack gear plate in the reversing of the bed.

6, In a mechanical movement, the combination of a reciprocating bed member, of an endless internal rack gear member suspended from said bed and having vertical movement independent of the bed, a driving pinion mounted'to rotate continuously in the same direction and engaging said internal rack gear, a control bar carried Within said internal rack, a riding roll mounted on the shaft of the driving pinion, reversing means for said bed, and spring means for equalizing the contact pressure on the Working surface of the control bar.

7. In a mechanical movement, the combination with a reciprocating bed member and a frame in. which said bed reciprocates, of an endless internal gear rack suspended from said bed and having vertical movement independent of said bed, a main driving pinion mounted to rotate continuously in the same direction and meshing with said internal gear rack, a control bar carried by the rack and within the same, a riding roll mounted on the shaft of the drive pinion, and rotatable thereon, and means for holding the control bar against the riding roll while traveling below the same, said means including a rocking lever pivotally mounted intermediate its ends and connected to the underside of the reciprocating bed, and one end pivotally connected to the said, internal gear rack member, an anchor arm rigidly secured at one end to said bed, and a compression spring connected at one end to the other arm of the rocking lever, and at its opposite end to the free end of the anchor arm.

JOHN WILLIS WEAVER. 

